Subspace Identification of Transfer Function Models for an Unstable Bioreactor

This work deals with the identification of transfer function model of an unstable bioreactor by a subspace-based identification method. The data set is generated from the simulated closed loop system by giving a random signal at the reference signal. The linear system matrices are estimated through the Multivariable Output Numerical algorithms for Subspace State Space System Identification (MON4SID) algorithm. The delay is estimated directly from the input–output data by the impulse response method. The identified First Order Plus Time Delay (FOPTD) model is compared with the locally linearized transfer function model derived around the unstable operating point. A Proportional Integral Derivative (PID) controller is designed for the identified model using the equating coefficient method. The closed loop servo and regulatory responses show that the model identified by MON4SID is similar to the linearized model and the optimization method.     

CCII-based PID controllers employing grounded passive components

In this paper, both of current-mode and voltage-mode proportional plus integral plus derivative (PID) controllers employing the second-generation current conveyors (CCIIs) as active elements are developed. The presented novel PID controllers have grounded passive elements that do not need passive element matching, and realize independently adjustable PID parameters. Thus, it is easy to implement these PID controllers in integrated circuits. Several computer simulations are presented to demonstrate the behavior of these proposed PID controllers.     

Development of the Control System of V-groove Ultra-precision Machining Machine Tool

The control system of micro V-groove machining CNC machine was developed with Qt application tool.This paper described the micro V-groove processing technology,the control system hardware platform composed of " IPC+PMAC",and the CNC software for V-groove machining.The various functional modules in the software were developed on the platform of windows,and the part of motion control of the CNC software was programmed by calling PMAC’s motion control functions.To achieve a visual effect of the numerical control interface and obtain the real situation of the processing on ahead,an important simulation module was also completed by using QOpen GL.The system can effectively control the running of the machine and translate the NC code into 3-D image before processing,which is very helpful for actual production.     

The evolution of different neuronal control structures for autonomous agents

The use of evolutionary methods to generate controllers for real-world autonomous agents has attracted recent attention. Most of the pertinent research has employed genetic algorithms or variations thereof. Recent research has indicated that the presence of epistasis drastically slows down genetic algorithms. For this reason, this paper uses a different evolutionary method, evolution strategies, for the evolution of various (complex) neuronal control architectures for mobile robots inspired by Braitenberg vehicles. In these experiments, the evolution strategy accelerates the development process by more than an order of magnitude (a few hours compared to more than two days). Furthermore, the evolution strategy yields the same efficacy when applied to receptive-field controllers that require many more parameters than Braitenberg controllers. This dramatic speedup is very important, since the development process is to be done in real robots.     

On the design and properties of multivariable dead time compensators

The design problem of multivariable dead time compensators for MIMO systems with multiple dead times is considered. Analytical design aids which take into account the stability and sensitivity properties of these systems are presented. Conditions for practical stability, estimates on allowable tolerances in process models and methods for determining controller gains are derived. Based upon sufficient conditions, these methods lead to conservative gains. The extent of conservation is related to the amount of computational effort involved in each method and to the available plant information. It is shown that the type of dead time compensator treated here cannot be applied to unstable processes. Diagonal dominance theory is used to derive some of the results. Illustrative examples demonstrate the main results.     

Finite-dimensional regulators for a class of infinite-dimensional systems

We show that the ‘direct approach’, developed by the author for stabilization of certain classes of distributed parameter systems, can be extended to cover regulation problems as well. An iterative design algorithm is presented, together with proof that the algorithm will converge after a finite number of steps. The procedure is illustrated with an example of a constant disturbance acting on a delay system.     

Stability analysis of switched systems using variational principles: An introduction

Many natural and artificial systems and processes encompass several modes of operation with a different dynamical behavior in each mode. Switched systems provide a suitable mathematical model for such processes, and their stability analysis is important for both theoretical and practical reasons. We review a specific approach for stability analysis based on using variational principles to characterize the “most unstable” solution of the switched system. We also discuss a link between the variational approach and the stability analysis of switched systems using Lie-algebraic considerations. Both approaches require the use of sophisticated tools from many different fields of applied mathematics. The purpose of this paper is to provide an accessible and self-contained review of these topics, emphasizing the intuitive and geometric underlying ideas.     

可编程序控制器在火电厂翻车机卸煤系统中的应用

介绍了日本OMRON公司C200H型可编程序控制琴在火电厂翻车机卸煤系统中自动控制的系统设计与应用。     

An object-oriented approach to Computer Integrated Systems

In recent years computers have been incorporated into large scale systems such as nuclear plant, flight control, and manufacturing systems. Such Computer Integrated Systems (CIS) normally consist of heterogeneous subsystems. The integration of heterogeneous subsystems requires that the subsystems be portable, inter-operable, and integrable at both software and hardware levels so that the integrated system should function properly. Objects and nets are proposed as the atomic elements of CIS's. An object is defined as a computational model of an arbitrary entity. Then three representation schemes of an object are introduced: algebraic, modular, and graphical. Two operations on objects,Composition andUnion, are introduced as means of combining two objects into a larger one. As an application of this approach, a Computer Integrated Manufacturing (CIM) system is represented as a network of objects.